Power driven rotary tooth brush or the like



Dec.12,1939.- J, A TH MME$ 2,183,415

POWER DRIVEN ROTARY TOOTH BRUSH 0R THE LIKE Filed May 5, 193? z Sheets-Sheet 1 Filed May 5, 1937 J. A. THOMMIES POWER DRIVEN ROTARY TOOTH BRUSH OR- THE LIKE' HIE 2 Sheets-Sheet 2 reactants-11 1939" i I arcane nnrvm some! room nnusn mm a. 'lhommes, Chime, m. mnem ic s, 1937, Serial No. 140,781

My inventionrelates to power driven brushes or the like,--more particularly to electrically' driven rotary instruments, such as tooth brushes or flnger nail polishers, and has for an object the provision of a simple, reliable, and inexpensive device or. thischaracter.

Power driven rotary brushes or the like for cleaning andpolishing teeth, finger nails, etc.,

have heretofore been provided in which an electric motor is connected through suitable gears and flexible shafts to a rotatable-brushing or polishing element. Such devices as heretofore constructed are rather limited in their application due to the fact that speed variations may be accomplished only byrelatively intricate and cumbersome gearing arrangements, or by providing relatively expensive variable speed motors.

In the application oi. rotary brushes or similar instruments to the teeth, gums, 'or finger.

nails, injury of the teeth, etc., may accidentally occur due to improper manipulation oi a positively driven instrument. Injuries of this character may be to a large extent eliminated by providing a slip drive between the brush and the 'motor which eflects positive drivev oi the 'brush only so, long as the load on the brush is less than a predetermined value and which permits the slipping between the brush and the motor when an obstruction is encountered.- It

easily adjustable to providefvarying speeds oi rotation in 'either or two directions, and whichissimple and'compact in its construction. I

- InJ-carrying out my invention in one form, I

provide; a power driven tooth brush comprising is, accordingly, a further object oimy invention to provide a rotary power driven instrument of this character which is provided with slidable friction driving means, which is quickly and a handle'ahaving a hollow head on one end and a drive shaft-journaled in thehandle tor rotary and axialmovement with respect thereto; one end of the drivejii'shait extending into .the hollow I" head and carrying a driving members One wall of the hollow head is provided with an aperture 45 tatably supporting a brush, which driven memin which-is ioumaled 'ajdriven member for rober is supported in frictional engagement with the driving member to provides frictional driving connection therebetween, andmeans are provided for axiallymoving one oi the irictionally engaging members to adjust the driving connection. 1

- More particularlm'I provide 'a, driving motor connected through a flexible shaft to one end or the drive shaft for rotating the same, and

the brush, and adjusting to vary the speed scum. -(CI. 15-28) ,the other end of the drive shaft which extends into the hollow head of thehandle is providedwith a driving wheel, the periphery oi. which carries a friction ringiormed of rubber or similar material. The hollow head is provided with 5 an open side in which is disposed a closure member for rotatably supporting a driven member, which comprises a disc having a flat face and a socket for detachably supporting a brushing element that extends outwardly from the closure 10 member. The friction ring on the driving wheel frictionally engages the flat roughened iface oi the disc-like driven member to'provide a slippable driving connection between the motor and v v tomove' the drivin wheel radially across the facefo ffthe disc so as directionoi rotationof the brush. Theehgaging pressure between the drivin'gand driven members'may be controlled by adjusting the closure member so as to move I the driven member axially toward or away from the periphery of the friction ring on the driving member. 95

For a more complete understanding oi my; invention, reference should now be had to-the drawings in which:

. Figure l is an elevational view to illustrate the constructional details;

- Fig. 2 is an enlarged fragmentary sectional view of the device shown in Fig. 1;

- Fig. 3 is a fragmentary-enlarged sectional view a oi amodifled iormof rotary instrument embody ing my invention; o i

Fig. 4 is a i'ragmentary sectional view of a still further embodiment otmy invention; and

Figs. 5 to 10, *inclusive, are detail views or various massaging, polishing, or abrasive elements which may be utilized in place otthe brushing element shown in Figs. land 2,;

Referring now to Fig. =1,-1 have shown my.

. invention as applied to an electric tooth brush '4 comprising a driven motor I 0. which 'i's preiere ably 'a constant speed motor of thetyp'egw'ell 1' known in the-art and which is provided with a suitable tumbler switch H for controlling the energization oi the motor, the external termi-fgu v 'nals oi the motor being formed as prongs l2, 4 so that the motor may be plugged directly intoa wall socket, the prongs I2 forming both'anp electrical connection and .a mechanical support the-motor A b m lull! described means are provided for 15 effecting relative axiaL-movement between the a {handle and the drive. ,s',

or an electric tooth brush' embodying my invention, portions being broken away in order more clearly hereinafter, the motor shaft is connected to one end of a flexible shaft 2, which is of a type well known in the art and which is disposed within a flexible conduit or casing l4, and the opposite end of the flexible shaft I2 is connected to a drive shaft i5-journaled within a handle l2, the opposite end of the drive shaft ll being driv ingly connected to a brush element II which extends outwardly from one wall of a hollow head formed on the end of the handle l2. As will also be more fully described hereinafter, an adjustable coupling member I2 is provided for connecting the handle 12 to the flexible conduit or casing i4, and a cylindrical insulating bracket 5 22 serves to connect the conduit or casing H to the frame or casing of the motor l2,

Referring now to Fig. 2, in which I have shown what I now consider to be a preferred embodi- -ment of my invention, it will be seen that the motor |2 includes a rotatable shaft 2| which is bifurcated or slotted toreceive one end of a coupling member 22, the opposite end of which is connected in anysuitable manner, preferably by'brazing, 'to one 'Bllil 'b! the flexible shaft I2 which extends intohi'socket formed in the end of the member 22. As shown, the shaft 2| and the coupling member 22 are provided with cooperating apertures'for receiving suitable screws 22, the shaft 2| and the screws 22 being insulated from the coupling member 22 by a pair of insulating plates 24 arranged on opposite sides of'the member 22 and by a pair of cylindrical insulating members 22 which surround the screws 22. I as Adjacent the other end of the flexible shaft I2, I provide a second coupling member 22, one end of which is provided with a socket into which the flexible shaft l2 extends, the other end of the coupling 22 being provided with a similar socket 49 for receiving theextending end of the drive shaft II, which is journaled-for axial and rotary movement in a cylindrical bearing member 21 which extends substantially the length of the handle l2. As shown, the opposite end of the handle I2 is engages the handle l2, and the end of the drive shaft it which extends into the hollow head 22 is provided with a driven member or wheel 22 which carries ,on its periphery a friction ring 22,

provided with a hollow head 28 which threadedly preferably formed of rubber or similar resilient material. Also supported in the hollow head 22 is a disc-like driven member 2|, the upper flat face of which \s arranged frictionally to engage the ring- 22, the driven member 2| being rotat ably journaled ina closure member 22 which is threaded, -as,.'shown, addustably to engage cooperating threads inone wall of the closure member 22. In order to'reduce-to a minimum the friction between the driven member 2| and so the closure member 22, I provide suitable antifriction means, such for example as the ball bearing means 22 interposed between the upper face of the closure member 22 and a portion of the drivenmember 2|.

05 As shown, the driven member 2| is, provided with a downwardly extending cylindrical portion 24 which is Journaled in an aperture 22 in the closure member 22, and this downwardly extending'portion 24' is provided with a socket for 70 receiving the shaft 22 of the brushing element I'll; This shaft '22 is provided intermediate its ends with a ball-like spherical portion 21 adapted to be engaged by a plurality of spring fingers,

which'extend downwardly from the tubular por- 1'; tion 24 of the driven member 2|. It will be un- .2 area-slog,

mama com-8e, that the span fingers u q are sumciently resilient'to spread whenever the shaft of the brushingelementn is forced -upwardly into the socket in the portion 24 and to positively grip the spherical portion 21 so as to 5 hold the brushing element- I! in the position shown in Fig. 2. As will be explained more fully in connection with Fig. 7, the upper portion of the shaft 22 and the socket in the portion 24 of the driven element 2| are non-circular so as to 10 v prevent relative rotation between the driven member 2| and the brush, and so as to provide a driving connection therebetvveen.

It will be apparent now that when the shaft II is rotated, the frictional engagement of the ring 15 22 with the flat'face of the driven member 2| eflects rotation of, the driven member 2| and-the brushing element l1, and it will also be apparent that the speed at which the driven member 2| is rotated may be adjusted" by moving the shaft l5 axially so as to move the ring 22 radially across the face of the driven member 2| Thus, when the ring 22 engages the driven member2| adjacent its outer edge, a minimum speed of rdtation of the driven member is obtained, and

when the ring 22 engages the driven member 2| adjacent the center thereof, a speed of rotation is obtained. Likewise, it will be appar-' ent that if the ring 22 ismoved across the center of the member 2|, the direction of rotation-of 80 the driven member 2| will be reversed, and the speed of rotation in this reversed direction may i be varied from' a maximum to a-minimum' by moving the ring 22 toward the outer periphery of the driven member 2|.

, Since the driven member 2| is carried by the closure member 22 and the. hollow head 22 which are, in turn, supported by thehandle |2 and since the driving wheel 2|.and its friction ring 22 are supported on the shaft II, it will beevi 40 dent that movement of the'friction ring 22 across the driven member 2| may. be accomplished simply by effecting relative axial movement between the handle l2 andthe shaft II;

In order to accomplish this relative axial r movement between the shaft l2 and-the handle I2, I provide the adjustable coupling means indicated by reference numeral l2 in; Fig. 1. As

shown in Fig. 2, this adjustable coupling means it constitutes a pair of cylindrical members 22 50 and 42, the member 22 being. internally threaded,

as shown, adjustably to engage co-operatinl; threads on the handle l2 andexternally threaded, as shown, to engage cO-op rating internal threads on the member 42. As will be more fully ex- 55 plained hereinafter, the co-operati'ng members 29 and 42 are permanently connected together after assembly of the device by spinningdown the left-hand edged the member 42 tightly-to engage the member, as indicated by the ref,-

abuttingly to engage one-side of the enlarged portion 42 so as to prevent axialmovement of the shaft i5 relative to the members and.

Similarly, the member 42 is provided with an inwardly extending shoulder44 which co-operates with the portion 42 of thercoupling member 22 to prevent axial movement 'ofthe shaft IS in the opposite direction relative to members 22 and 42.

Adjacent its right-hand end the member 42 is provided with a pair of outwardly extending concentric ears -ll and It which are extends a sleeve-l" rigidly secured to oneend of radially toform a cylindrical socket onto which the conduit M, which conduit surrounds the flexible shaft [3. In order tofaciIItate assembly of the device, the ear 4! is initially formed, as indicated by' the broken lines, and after assembly of the sleeve 41 in the cylindrical socket between m" the ears" and ,the ear ll is spun inwardly so as to coI-operate with the flange II on the end of'thesleeve ll permanently to position the sleeve 41 inthe cylindrical socket while permit ting rotation ofthe member 40. relative to the sleeve 41.

Adjacent its .other end, the flexible conduit 14 is flanged, as shown, co-operatively to engage the cylindrical bracket .23 which is formed of insulating material and which may be secured to the frame of the motor 13 in any desired manner, as for example'by the bolts 43.

It will now be apparent that by reason of the above described construction of the coupling means formed by themember's 33 and 4 0, the coupling means, together withthe handle i3, may

be rotated as a unit relative to the flexible con-' duit ll andthe drive shafts l3 and i soas to provide different angular positions of the brush I'l during a tooth brushing operation without varying the speed of rotation of the brush- Similarly, it will be apparent that simply by rotating the coupling means comprising. the members 39. and 43 relative to the handle it, the handle it, by reason of its threaded connection with the member 39, maybe moved in a lefthand direction from the extreme right-hand position shown in Fig. 2, and thus-movement of the friction ring 30 across the flatface of the driven member 3i may be efl'ected so as to vary the speed and the direction of rotation of the driven member 3|. Likewise, the engaging pressure between the friction ring 30 and-the driven member 3i may be adjusted-simply by rotating the closure member 32, the threaded connection between the hollow head 28 and the closure member 32 providing for inward andoutward' movement of the closure member upon rotation-thereof. In order to prevent accidental rotation of the closure member 32, I provide a suitable set screw 49, the

innermost end of which is arranged to engage.

the closure member 32 so as to lock the member in any desired position.

In addition to its compactment, simplicitmand closure ease of adjus ment, afurther advantage of my I improved power driven'instrument resides in its the following manner. In order to assemble the [3 .has already been secured, as by brazing, may.

then be secured-to the extending end of the shaft SIS, as for example by inserting a cross pin-5d ber 26 and the shaft 15, and the pin 53 maybeease of assembly which may be carried out "in various parts of the co-operating relation shown in Fig. 2, the drive shaft I5 is flrstinserted from .the left-hand end; of the cylindricalbearing I! I in the handle it, and the member 3! isthreaded ontothe right-haird'end of the handle 16. Thecoupling member 28, to which the flexible shaft into co-operating apertures in the-.coupling'mem permanently secured in the positionshown by peening over or staking the .edges of theaperture in the coupling member. The next step in.

the assembly of. the device consistssimply'iof threading the member 40 onto the member 39 andspinnigg the portions. ll of the member 40' inwardly so as'permanently. to engage the member 39, and theflexible conduit may then he rpm different type. of coupling-means is provided;

flange 43 on the sleeve 41 is disposed in the'cylindrical socket in the right-hand end'of the member .33, whereupon the cylindrical ear I! may be spun inwardly to the position shown in Fig. 2. At this stage'of the assembly itxwill be under-- slipped over the flexible shaft is so-thatthe" of the motor, as for example bythe screws 23.

In order to complete the assembly, it is now only necessary to slide the bracket in the righthand direction until the inturn'ed flanges thereon engage the outwardly turned flanges on the conduit, and it will be understood that the lengths of the various parts are so arranged that when these flanges engage, the outwardly flanged open end of the bracket '20 will engage the-frame or casing of the motor l0 and may be secured thereto bythe-bolts l9. 4

Assembly of thehead end of the brush may now be accomplished simply by: threading the hollow head 28 onto the left-hand end of the handle it bypositioning the driven member 3| and the ball bearings 33 on the closure member 32; and finally threading the closure member 32 into the open side of the hollow'head 28. The device. isnow completely assembled, except for the brush element I! which, as describedabove.

may simply be inserted through the aperture in the closure member- 32 and pressed into the socket in the downwardly extending portion. 34

of the driven member 3|.

In Fig. 3 I have shown a power driven rotary ,tooth brush provided with slippage friction driving means embodying my invention, the device here shown being adapted only for constant speed operation. As shown in Fig.- 3, handle-5i of thedevice is provided with a hollow-head 52 threads. The closure member 53 is'similar to the closure member 32 described in connection --with Fig. l, in that it is provided with anaperture and rotatably supports a driven member 65. which is'arranged-frictionally to engage a drivingwheel 56 carried on .the end of a drive 1 shaft 51 which extends through, andis journaled in, a cylindrical bearing 58 in the handle 5!. In this embodiment ofnmy invention the driven ,member'iS supports a. friction ring 59 formed of rubber or suitable resilient. materia1','the periphery of which engages a substantially flat face of the driving wheel '56,:and, if desired, this flat face of .the drivingwheel 56 may be serrated or otherwise roughened soas to increase the. frichaving an open sidein which a closure member 7 p53 is" disposed, the hollow head 52 and the closure member 53 being provided with co -operating tiolial eng'agement with the rubber ring 59. It will, 'of course, be understood that the flat faceof the driven member 3| in the embodiment shown in Fig. 2'may be similarly serratedor-roughened if desired. In this embodiment of 'my invention, -relativeaxial movement between the shaft 51' and the handle ii, is utilized only to vary the frictional engaging pressure between the driving and .driven members and, accordingly, a somewhat As shown, the coupling means here provided comprises a coupling member 6| which is internally threaded co-operatively to engage external threads on the right-hand end, of the handle 6|, and the right-hand end of the coupling member is provided with spaced apart concentric ears 62 and 63 which are substantially identical with the ears 46 and 45 in the embodiment shown in Fig. 2, the ear 63 being adapted to be spun over, as shown, in order to co-operatively engage a flange 64 on a sleeve 65 which is permanently secured to a flexible conduit or casing 66 surrounding a flexible drive shaft 61. It will, of

- course, be understood that the opposite ends of thereof, whereupon the lock nut 12 and the the flexible shaft 61 and the conduit 66 are connected to the shaft of the electric motor in the identical manner described above in connection with Fig. 2. Intermediate the flexible shaft 61 and the drive shaft 51 I provide in this embodiment of my invention a coupling member 66 which is permanently secured, as by brazing, tothe flexible shaft 61 and which is provided with a socket 69 shaped to receive a non-circular or rectangular tongue 10 which extends outwardly from the drive shaft 51. The coupling member 68 is provided, as shown, with a portion'of enlarged diameter, one side of whichis arranged adjacent an inwardly extending shoulder 1| on v the coupling member 6|, and a lock nut 12 is provided which may be threaded into the cou pling member 6| to a position adjacent the other side of the enlarged portion of the coupling member 68.

In assembling this embodiment of my inven-' tion, the flexible shaft 61 is first brazed to the coupling member 66 and then inserted into the coupling member 6| from the left-hand end handle 5| may be threaded into the coupling member 6| and the drive shaft 51 inserted from the left-hand end of the handle 5| and rotated until the non-circular tongue 10 engages the socket 69 in the end of the coupling member 68. The assembly of the flexible conduit 66 with respect to the coupling member 6| and the connection of the flexible shaft 61 to the motor may be carried out as described above in connection with Fig. 2, and the assembly may then be completed by threading the hollow head 52 onto the hollow handle 6| and inserting the driven member 55 and the closure member 66 in ,the hollow head.

In Fig. 3 the handle 6| is shown in the position to which it is initially threaded during assembly of the device. In this position of the handle 6| sufficient clearance is left between theend of the tongue 10 and'the bottom of the'co-o rating socket in the coupling member 66, as wel as between the shoulder 13 on the driving wheel 66 and the flanged end of the bearing member 66, to permit axial movement of the shaft 51 with respect to the handle 5| so as to facilitate insertion of the driven member 55. After the driven member 55 has been inserted, the coupling 6| may be rotated so as to move the handle 5| in a right-hand direction and thereby cause the friction ring 69 on the driven member to engage tightly the fiat face 66 of the driving wheel 66,- the tongue 10 being thus urged into abutting engagement with the bottom of its co-operatlngv socket.

In Fig. 4 I have shown a still further embodie ment of my invention which is substantially identical with the embodiment shown in Fig. 3, 7 except that the handle 6| is. provided with a p ball-like spherical portion 66 adapted to be ensaid handle for rotary and axial movement with respect thereto, a handle retaining coupling hollow head 16, the open side of which is disposed at a slight angle to the axis of the shaft 61 so that the closuremember 15 and the driven member 16 supported thereby are disposed in other than perpendicular relation to the shaft 61. In this embodiment of my invention, the driven member 16 carries a friction ring 11, the outer periphery of which is tapered, as shown, so as to engage the serrated face 6| of the driving wheel 66. In some cases this angular relation of the driven member, which of course carries the brushing element, may be found more satis factory to the user of the instrument.

While I have described my invention thus far as particularly applied to a rotary tooth brush, it will, of course, be apparent that various other working elements may be utilized in place of the brushing element |1 shown in Figs. 1 and 2. Thus, for example, a suction cup 16 of the type shown in Figs. 5, 6, and 7 may be substituted for the-brush 1, suction cups of this character being useful in massaging the gums. As shown, the suction cup 16 is provided with a non-circular or substantiallyrectangular shaft 19 and with a files, such for example as the elements 66 and 66 shown in Figs. 9 and 10, respectively, may be utilized. The abrasive element 66 shown in Fig. 10 is provided with a peripheral groove 65, the bottom surface of which forms the abrasive working surface, the groove serving as a guide for finger nails or other members to be shaped or treated by the abrasive surface.

While I {have shown particular embodiments of my invention, it will be understood, of course, that I do not wish to be limited thereto since many, modifications may be made, and I, therefore, contemplate by the appended claims to cover any such modifications as fall within the true spirit and scopeof my invention.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. Ina power driven tooth brush or the like, the combination of a handle having a hollow head on one end thereof, said hollow head having an aperture in one wall, a" drive shaft journaled in means Journaled on said shaft in fixed axial relation thereto and adjustable relative to said handle to cause relative axial movement between said handle and said shaft, one end of said shaft extending into said hollow head, a driven member journaled in said aperture for rotatablysupporting a brush, a driving member fixed on said extending end of said shaft, said driven member comprising a wheel having -a substantially flat face, an annular friction element carried by said driving -member for peripherally enga ing the fiat face of said wheel to provide a frictional dr'iving .connection therebetween, and means for moving said driven member axially to adjust the engaging pressure between said annular element and saidface of said wheel.

2. In a power driven tooth brushorthe like, I

the combination of a handle having a hollow 2,188,415 'of a person using said brush and said hollow head having an aperture in one wall, a drive shaft journaled in said handle for rotary and axial movement with respect thereto, one end of said shaft extending into said hollow head, a

driven member journaled in'said aperture for rotatably supporting a brush, a driving member fixed on said extending end of said shaft, 'said driven member comprising a wheel having a substantially flat face, said driving member peripherally engaging the flat face of said wheel to provide a frictional driving connection therebe- ,tween, and a handle retaining couplingmeans adjustably engaging the end of said handle oppo- I the combination of a handle having a hollow' head on one end thereof, said head having an open side, a drive shaft journaled in said handle for rotary and axial movement with respect thereto, one end of said shaft extending into" said hollow head, a driving member on said end of said shaft, a closure member for said open side having an aperture therethrough, a driven;

member iournaled in said aperture and restrained from lateral movement therefrom and frictionally engaging said driving member, said driven member being adapted forrotatably supporting a brush the working portion of which extends outwardly from said closure member,-

said closure member being adjustable into and out of said open side to vary the enga liia pressure between said driving and driven members, and means on said handle for effecting axial movement of said drive shaft to vary the position of said driving and driven members.

mission.

4. Ina power driven tooth brush or the like, the combination of a handle having a hollow head on one end thereof, said head having an open side and being suiflcientlysmall for insertion into the mouth of a person using said brush,

a drive shaftjournaled in said handle for rotary and axial movement with respect. thereto, one end of said shaft extending into said hollow head, a driving member on said end of said shaft, a

closure member for said open side having an aperture therethrough, a driven member journaled in said aperture including a disc-like portion' one face of which frictionally engages the periphery of said driving member, said driven member' also including a shaft having a socket for supporting a brushthe working portion of which extends outwardly from said closure memher, and a handle retaining coupling means adjustably engaging the end of said handle opposite from said hollow head, said coupling means being joumaled on said shaft in fixed axial relation thereto and being adjustable relative to said handle to adjust said handle and said shaft axially with respect to each other to move said driving member radially across said disc an thereby vary the speed of said brush.

'5. In a'power driven tooth brush,' the combination with a handle having a rotatable drive shaft journaled therein, of a movable member cooperatively related to said shaft and said handle normally'to prevent relative axial movement and movable, by the operator to cause said movement, a driven member journalled in said handle, a-variable speed transmission between said shaft and said driven member and responsive to said relative axial movement to vary the speed of said driven member and manually movable adjusting means on said handle and accessible'to the op- "erator for effecting movementof said driven member laterally with respect to said shaft to' vary the driving characteristics of said trans- JoiiN a momma. 

